Q. Given the function f(x)=−65x2+51, then what is f(2x) as a simplified polynomial?Answer:
Substitute x in f(x): Substitute 2x into the function f(x). We need to replace every instance of x in the function with 2x. f(2x)=−(65)(2x)2+(51)
Simplify square of (2x): Simplify the square of (2x). We need to square the term (2x) to get (2x)2. (2x)2=(22)(x2)=4x2
Substitute squared term: Substitute the squared term back into the function.Now we replace (2x)2 with 4x2 in the function.f(2x)=−(65)(4x2)+(51)
Multiply coefficients: Multiply the coefficients.We need to multiply the coefficient −65 by 4.−65×4=−620=−310
Write simplified polynomial: Write the simplified polynomial.Now we have the coefficient for x2, we can write the simplified polynomial.f(2x)=−310x2+(51)
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